• 제목/요약/키워드: time schedule

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소나무와 리기다소나무 평소각재(平小角材)의 고온건조(高溫乾燥) (High-temperature drying of Pinus densiflora and Pinus rigida dimension lumber)

  • 박문재;정희석
    • Journal of the Korean Wood Science and Technology
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    • 제15권2호
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    • pp.53-66
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    • 1987
  • Korean red pine (Pinus densiflora S. et. Z.) and pitch pine(Pinus rigida Mill) $5{\times}10cm$ dimension lumber were dried in a kiln providing a cross-circulation velocity of 5 m/sec at dry-and wet-bulb temperatures of 116 and $71^{\circ}C$, followed by 3 hours at 91 and $85^{\circ}C$. Compared to dimension lumber dried lumber were as follows. 1. To dry to 10 percent moisture content, the high-temperatures schedule of Korean red pine and pitch pine lumber took less than one seventh the time required by the conventional kiln drying schedule. 2. High-temperature drying rate and conventional drying rate to 10 percent moisture content of Korean red pine lumber were 2.75 and 0.35%/hr, and those of pitch pine lumber were 3.38 and 0.46%/hr respectively. 3. Compared to lumber of both species on conventional schedule, moisture gradient of high-temperature lumber was greater. 4. Compared to lumber on conventional schedule, maximum surface checking of high-temperature lumber of both species was severer, and maximum end checking of high-temperature lumber of both species was similar to that of lumber on conventional schedule. 5. Compard to lumber on conventional schedule, Korean red pine lumber dried at high temperature showed more honeycombing, but pitch pine lumber dried at high-temperature showed significantly slighter honeycombing. 6. Compared to lumber on conventional schedule, the high-temperature lumber showed less warping lumber of both species. 7. Collapse and casehardening of Korean red pine and pitch pine lumber on both scheules were slight.

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한국 개(個)교회기록물의 기능분류 방안 (A Study constructing a Function-Based Records Classification System for Korean Individual Church)

  • 마원준
    • 기록학연구
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    • 제10호
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    • pp.145-194
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    • 2004
  • Church archives are the evidential instruments to remember church activity and important information aggregate which has administrative, legal, financial, historical, faithful value as the collective memory of church community. So it must be managed necessarily and the management orders are based on the Bible. The western churches which have a correct understanding about the importance of church records and management order have taken multilateral endeavor to create, manage church archives systematically. On the other hand, korean churches don't have the records management systems. Therefore, Records created in individual church are mostly managed unsystematically and exist as 'backlogs', finally, they are destructed without reasonable formalities. In those problems, the purpose of this study is to offer the way of records classification and disposition instrument with recognition that records management should be done from the time of creation or previous to it. As a concrete device for them, I tried to embody the function-based classification method and disposal schedule. I prefer the function-based classification and disposal schedule to the organization and function-based classification to present stable classification and disposal schedule, as we can say the best feature of the modern organization is multilateral and also churches have same aspect. For this study, I applied DIRKS(Designing and Implementing Recordkeeping Systems) manual which National Archives of Australia provide and guidelines in ICA/IRMT series to construct the theory of the function-based classification in individual churches. Through them, it was possible to present a model for preliminary investigation, analysis of business activity, records survey, disposal schedule. And I took an example of 'Myong Sung Presbyterian Church' which belong to 'The Presbyterian church in Korea'. I explained in detail codifying process and results of preliminary investigation in 'Myong Sung Presbyterian Church', analysis of business activity based on it, process of presenting the function-based classification and disposal schedule got from all those steps. For establishing disposal schedule, I planned 'General Disposal Schedule' and 'Agency Disposal Schedule' which categorized 'general function' and 'agency function' of an agency, according to DIRKS in Australia and ICA/IRMT. And for estimation of disposal date I had a thorough grasp of important records category presented in 'Constitution of General Assembly', interview to know the importance of tasks, and added examples of disposal schedule in western church archives. This study has significance that it was intended to embody 'the function-based classification' and 'disposal schedule' suitable for individual church, applying DIRKS in Australia and ICA/IRMT on absence of the theory or example which tried to present the function-based classification and disposal schedule for individual church. Also it is meaningful to present a model that can classify and disposal real records according to the function in individual church which has no recognition or way about records management.

Implementation of the VHOE-based Multiview 3D Display System by using Optimized Exposure-Time Scheduling Scheme

  • Kim, Seung-Chul;Gu, Jung-Sik;Kim, Eun-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.883-886
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    • 2002
  • A new exposure time scheduling scheme to implement the optimized photopolymer-based VHOE is proposed and using this method, the 8-view VHOE system is experimentally developed. The CGS dependence on the exposure energy is mathematically modeled using the fourth-order polynomial function and using this model optimized exposure-time schedule for recording the given multiple gratings in the photopolymer is calculated. In addition, basing on this suggested exposure-time schedule, 8-view VHOE is finally implemented and its performance is discussed.

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출발시간제약이 존재하는 동적 복합교통망의 K최소시간경로탐색 (A K Least Time Paths Searching Algorithm for Time Dependent Intermodal Transportation Networks with Departure Time Schedule Constraints)

  • 조종석;신성일;문병섭;임강원
    • 대한교통학회지
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    • 제24권3호
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    • pp.167-176
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    • 2006
  • 출발시간제약이 존재하는 통합교통망의 최소시간경로탐색은 도착수단의 도착시간 수단간 환승시간, 대기시간 뿐만 아니라. 다음수단의 출발시간을 고려하는 것이 필요하다. 다수의 교통수단이 존재하는 통합교통망에서는 출발시간제약이 포함되는 경우가 매우 일반적인 현상이다. 이는 철도나 항공 등과 같은 대중교통노선들은 일정한 시간에 서비스를 제공하는 노선별 스케줄을 가지고 있기 때문이다. 본 연구에서는 이러한 출발시간제약조건이 존재하는 통합교통망을 통행시간이 시간대에 따라 동적으로 변화하는 상황에서 K개의 경로를 탐색하는 알고리즘을 개발하고자 한다. 그리고, 이러한 알고리즘개발을 위하여 유입링크기반의 전체경로삭제방식을 확대 적용하는 방안을 제안하며, 사례연구를 통하여 알고리즘의 활용성을 검토한다.

디스패칭 룰 기반의 Advanced Planning and Scheduling (APS) 시스템 활용 사례연구 (A Case Study on Application of Dispatching Rule-Based Advanced Planning and Scheduling (APS) System)

  • 이재용;신문수
    • 산업경영시스템학회지
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    • 제38권3호
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    • pp.78-86
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    • 2015
  • Up-to-date business environment for manufacturers is very complex and rapidly changing. In other words, companies are facing a variety of changes, such as diversifying customer requirements, shortening product life cycles, and switching to small quantity batch production. In this situation, the companies are introducing the concept of JIT (just-in-time) to solve the problem of on-time production and on-time delivery for survival. Though many companies have introduced ERP (enterprise resource planning) systems and MRP (material requirement planning) systems, the performance of these systems seems to fall short of expectations. In this paper, the case study on introducing an APS (advanced planning and scheduling) system based on dispatching rules to a machining company and on finding a method to establish an efficient production schedule is presented. The case company has trouble creating an effective production plan and schedule, even though it is equipped with an MRP-based ERP system. The APS system is applied to CNC (computer numerical control) machines, which are key machines of the case company. The overall progress of this research is as follows. First, we collect and analyze the master data on individual products and processes of the case company in order to build a production scheduling model. Second, we perform a pre-allocation simulation based on dispatching rules in order to calculate the priority of each order. Third, we perform a set of production simulations applying the priority value in order to evaluate production lead time and tardiness of pre-defined dispatching rules. Finally, we select the optimal dispatching rule suitable for work situation of the case company. As a result, an improved production schedule leads to an increase in production and reduced production lead time.

Minimum time path planning of robotic manipulator in drilling/spot welding tasks

  • Zhang, Qiang;Zhao, Ming-Yong
    • Journal of Computational Design and Engineering
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    • 제3권2호
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    • pp.132-139
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    • 2016
  • In this paper, a minimum time path planning strategy is proposed for multi points manufacturing problems in drilling/spot welding tasks. By optimizing the travelling schedule of the set points and the detailed transfer path between points, the minimum time manufacturing task is realized under fully utilizing the dynamic performance of robotic manipulator. According to the start-stop movement in drilling/spot welding task, the path planning problem can be converted into a traveling salesman problem (TSP) and a series of point to point minimum time transfer path planning problems. Cubic Hermite interpolation polynomial is used to parameterize the transfer path and then the path parameters are optimized to obtain minimum point to point transfer time. A new TSP with minimum time index is constructed by using point-point transfer time as the TSP parameter. The classical genetic algorithm (GA) is applied to obtain the optimal travelling schedule. Several minimum time drilling tasks of a 3-DOF robotic manipulator are used as examples to demonstrate the effectiveness of the proposed approach.

THE M/G/1 FEEDBACK RETRIAL QUEUE WITH BERNOULLI SCHEDULE

  • Lee, Yong-Wan;Jang, Young-Ho
    • Journal of applied mathematics & informatics
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    • 제27권1_2호
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    • pp.259-266
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    • 2009
  • We consider an M/G/1 feedback retrial queue with Bernoulli schedule in which after being served each customer either joins the retrial group again or departs the system permanently. Using the supplementary variable method, we obtain the joint generating function of the numbers of customers in two groups.

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이득 스케쥴을 이용한 항공기 자동조종장치의 구성 (The study of autopilot system with pre-designed gain schedule)

  • 장정순;박춘배
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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    • pp.613-618
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    • 1993
  • This paper presents the aircraft autopilot system with a pre-designed gain schedule. It is mainly consisted of the parameter estimation end the autopilot system design. For off-line parameter estimation, leastsquare methods are investigated. The design of a controller is done in frequenced domain using classical control method and it is designed to satisfy the predetermined requirement such as time constant and transient response. Finally, it is compared with a optimal regulator.

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분류표에서 사용하는 보조표에 대한 연구 (A study of auxiliary schedules in classification)

  • 정해성
    • 한국도서관정보학회지
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    • 제28권
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    • pp.193-218
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    • 1998
  • The purpose of this study is to analyze and compare of the structure of auxiliary schedules using in DDC, UDC, CC and BC. Auxiliary schedule whish are a n.0, ppended to schedule of all schemes of classification. They consist of items of form of presentation relationship, time, place, languages, racial, ethnic, national groups and persons and phase relation and the symbols of the different items can be added to classification numbers.

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표정속도 향상에 따른 기술동향 연구 (A Study on Technology Trend according to Schedule Speed Improvement)

  • 이훈구;이남형;최경선;편선호;엄기영
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.140-144
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    • 2011
  • As a result of that the domestic railway technology has been progressed as times go by, the 1st and the 2nd steps for Gyeongbu HSR at the speed of more than 300km/h, were completed and Honam HSR - its operational speed is 350km/h - is under construction. Additionally, As a part of the expressization project for general lines, the Seoul-Chuncheon route at the speed of more than 180[km/h] is under construction and the Jeolla route is under design. At present, 11 countries (e.g. France, Germany, Belgium, Italy, the Netherlands, Spain, England, Japan, China and Taiwan) including Korea have high speed railways operated at the speed of more than 300[km/h]. As shown in the above, the domestic railway has high speed trains as good as those of countries outside Korea, but the schedule speed, which is calculated by dividing distance to destination by time, is lower than that of overseas trains. For overseas railway, the ratio of schedule speed to the highest speed is above 65%, while that of domestic railways is over 50%. It shows a significant difference between them. It is expected that the schedule speed improvement will increase the number of train operation and line capacities than now, so it shall achieve smooth transportation flow and improve the passengers' satisfaction. In this paper we describe the necessity for the improvement of schedule speed, by analyzing foreign cases related to the improvement of schedule speed in order to satisfy the increasing traffic demand.

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